Prediction Research On Shielding Effectiveness Of Electronic Equipment Box

With the development of technology in today's world, more and more electronic equipments enter many aspects of people's lives, accompanied by electromagnetic radiation threatening human health. Electromagnetic compatibility (EMC) must be considered in the design of electronic equipments and products. EMC design is carried out against electromagnetic interference. Its aim is to ensure that electronic equipment can run safely in environment including electromagnetic interference, and electronic equipment won't produce radiation and interference which the outside world can't afford. Electromagnetic shielding can solve electromagnetic interference problem and protect electromagnetic environment. Shielding effectiveness is a technical index to measure effective shield. It is showed that matrix pencil method is an efficient real-time numerical calculation which has a great advantage on electromagnetic compatibility by studying many predictions of the shielding effectiveness.The traditional matrix pencil algorithm has some shortcomings in low SNR. For example, the calculation of numerical is unstable, and the accuracy of pole extraction is not high. In this paper, the traditional matrix pencil algorithm has been improved with inter-related processing method. Through theoretical studies, practical measurements, algorithm simulation and analysis of the results, it shows that the improved matrix pencil algorithm is more accurate than the traditional method in extracting poles, and has a higher degree of fitting with the original signal. Therefore, it verifies the superiority and correctness of the improved algorithm, and it provides a theoretical and algorithm basis for prediction of shielding effectiveness. Due to heat and other reasons, a small hole often needs to be opened in the box of the electronic equipment. And its discontinuity would reduce the shielding effectiveness of the box. Then, this algorithm is applied to predict the shielding effectiveness, in order to prove that changing hole size and the angle of incident wave has an impact on the shielding effectiveness. This study has guiding significance on the initial design and overall designing of electronic equipment box.